Letterman might be replaced by Colbert, but he won't be replicated

5:56 AM,
Apr. 11, 2014

In this June 9, 2009, file photo released by CBS, actress Julia Roberts laughs as she holds host David Letterman's hand on the set of the 'Late Show with David Letterman,' in New York. Letterman announced his retirement during a taping on Thursday, April 3. Although no specific date was announced he told the audience that he will leave his desk sometime in 2015. (AP Photo/CBS, John Paul Filo)